Submission #1219789

#	Time	Username	Problem	Language	Result	Execution time	Memory
1219789		thelegendary08	Joker (BOI20_joker)	C++17	39 / 100	634 ms	23752 KiB

Joker

#include<bits/stdc++.h>
#define pb push_back
#define mp make_pair
#define int long long
#define vi vector<int>
#define vvi vector<vector<int>>
#define pii pair<int, int>
#define vpii vector<pair<int, int>>
#define vc vector<char>
#define vb vector<bool>
#define mii map<int,int>
#define f0r(i,n) for(int i=0;i<n;i++)
#define FOR(i,k,n) for(int i=k;i<n;i++)
#define all(v) (v).begin(),(v).end()
#define rall(v) (v).rbegin(),(v).rend()
#define in(a) int a; cin>>a
#define in2(a,b) int a,b; cin>>a>>b
#define in3(a,b,c) int a,b,c; cin>>a>>b>>c
#define in4(a,b,c,d) int a,b,c,d; cin>>a>>b>>c>>d
#define vin(v,n); vi v(n); f0r(i,n){cin>>v[i];}
#define out(a) cout<<a<<'\n'
#define out2(a,b) cout<<a<<' '<<b<<'\n'
#define out3(a,b,c) cout<<a<<' '<<b<<' '<<c<<'\n'
#define out4(a,b,c,d) cout<<a<<' '<<b<<' '<<c<<' '<<d<<'\n'
#define pout(a) cout<<a.first<<' '<<a.second<<'\n'
#define vout(v) for(auto u : v){cout<<u<<' ';} cout<<'\n'
#define dout(a) cout<<a<<' '<<#a<<'\n'
#define dout2(a,b) cout<<a<<' '<<#a<<' '<<b<<' '<<#b<<'\n'
#define yn(x); if(x){cout<<"YES"<<'\n';}else{cout<<"NO"<<'\n';}
const int leg = 1e9 + 7;
const int mod = 998244353;
using namespace std;
const int mxn = 2e5 + 5;
vi adj[mxn];
signed main(){
	ios::sync_with_stdio(false);
	cin.tie(NULL);
	//ifstream cin(".in");
	//ofstream cout(".out");
	in3(n,m,q);
	vpii edges;
	f0r(i,m){
		in2(a,b); a--; b--; edges.pb(mp(a,b));
	}
	if(n <= 2000 && m <= 2000 && q <= 2000){
		while(q--){
			in2(l,r); l--; r--;
			vvi cadj(n);
			f0r(i,m){
				if(i < l || i > r){
					int a = edges[i].first; int b = edges[i].second;
					cadj[a].pb(b); cadj[b].pb(a);
				}
			}
			
			vi col(n, -1);
			vb vis(n);
			bool ok = 1;
			f0r(i,n){
				if(!vis[i]){
					vis[i] = 1;
					queue<int>q;
					q.push(i);
					col[i] = 1;
					while(!q.empty()){
						int node = q.front(); q.pop();
						for(auto u : cadj[node]){
							if(vis[u]){
								if(col[u] != 1-col[node]){
									ok = 0; break;
								}
							}
							else{
								col[u] = 1 - col[node];
								vis[u] = 1;
								q.push(u);
							}
						}
						if(!ok)break;
					}
				}
			}
			yn(!ok);
		}
	}
	else{
		int lo = -1; 
		int hi = m-1;
		while(lo < hi){
			int mid = lo + (hi - lo + 1) / 2;
			vvi cadj(n);
			f0r(i,m){
				if(i > mid){
					int a = edges[i].first; int b = edges[i].second;
					cadj[a].pb(b); cadj[b].pb(a);
				}
			}
			
			vi col(n, -1);
			vb vis(n);
			bool ok = 1;
			f0r(i,n){
				if(!vis[i]){
					vis[i] = 1;
					queue<int>q;
					q.push(i);
					col[i] = 1;
					while(!q.empty()){
						int node = q.front(); q.pop();
						for(auto u : cadj[node]){
							if(vis[u]){
								if(col[u] != 1-col[node]){
									ok = 0; break;
								}
							}
							else{
								col[u] = 1 - col[node];
								vis[u] = 1;
								q.push(u);
							}
						}
						if(!ok)break;
					}
				}
			}
			if(!ok){
				lo = mid;
			}
			else{
				hi = mid - 1;
			}
		}
		
		while(q--){
			in2(l,r); l--; r--;
			if(r <= lo){
				out("YES");
			}
			else out("NO");
		}
	}
	
	
}

• Subtask 1: 8 / 8
• Subtask 2: 25 / 25
• Subtask 3: 0 / 10
• Subtask 4: 0 / 22
• Subtask 5: 0 / 29
• Subtask 6: 6 / 6